[填空题]The past two decades have seen in the US an increase in the number of the newspapers but a decrease in their readership.

[填空题]The past two decades have seen in the US an increase in the number of the newspapers but a decrease in their readership.

[单项选择]Most of us have seen a dog staring at, sometimes snarling at, and approaching a reflection of itself. For most animals, seeing their own image in a mirror acts as a social stimulus. But does the dog recognize itself, or does the reflection simply signal a potential companion or threat This question is interesting for a number of masons. Apart from curiosity about the level of animals’ understanding, research on serf- recognition in animals has several benefits. It provides some insight into the evolutionary significance of this skill of serf-recognition and into the level and kinds of cognitive competence that the skill requires. Such research also indicates the kinds of learning experiences that determine the development of self-recognition. In addition, work with animals fosters the use of techniques that are not dependent on verbal responses and that may therefore be suitable for use with preverbal children.
The evidence indicates that dogs and almost all other nonhumans do not
A. whether dogs recognize themselves in mirrors
B. whether the grooming practices of chimps can be altered
C. whether nonhumans have a serf-concept
D. what her chimps change their behavior when a mirror is present

[单项选择]

Although recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently, more than 100 cities in the United States still have levels of carbon monoxide, particulate matter, and ozone (generated by photochemical reactions with hydrocarbons from vehicle exhaust) that exceed legally established limits. There is a growing realization that the only effective way to achieve further reduction in vehicle emissions -- short of a massive shift away from the private automobile -- is to replace conventional diesel fuel and gasoline with cleaner-burning fuels such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn more cleanly than gasoline, in part because they have fewer, if any, carbon-car-bon bonds and the hydrocarbons t
A. flawed because of the assumptions on which it is based
B. inapplicable because of an inconsistency in the critics’ arguments
C. misguided because of its exclusively technological focus
D. inaccurate because it ignores consumers’ concern